I also used the same method few months ago. But getting an average value is not much good for some applications. If you plot the readings you can see a large variance for some sensor readings. But here I only get variance of 0.02 degrees.

You are welcome. Actually there are lots to understand in this filter but it's hard without strong mathematics knowledge. That's why I tried to explain it simply as I can. But you can use the filter without understanding and get the results.

I was thinking about adding a selector switch for different voltages as you said. But I had to hand over this project according to the given specifications. Thank you for your suggestions. They will be really helpful for my future projects.